Calculation and Experimental Study of Axial Loading of Casing Based on the Phase Transition Effect During Curing of Ceme
- PDF / 2,443,852 Bytes
- 10 Pages / 595.276 x 790.866 pts Page_size
- 45 Downloads / 197 Views
RESEARCH ARTICLE-PETROLEUM ENGINEERING
Calculation and Experimental Study of Axial Loading of Casing Based on the Phase Transition Effect During Curing of Cement Slurry Yuqi Ding1
· Ye Lu1 · Jiahao Cheng1 · Min Luo1 · Ziwei Dai1
Received: 7 February 2018 / Accepted: 4 October 2020 © King Fahd University of Petroleum & Minerals 2020
Abstract In this paper, the casing strings of cement slurry during the curing period are taken as the research object in order to build a force model, with comprehensively considering the influence factors such as the phase transition heat transfer and volume change of the cement slurry during the curing period. The random contacts between casings and well walls were simulated by establishing a gap element between two phases of cement slurry. Formulas of axial loadings on the casings during curing of cement slurry were obtained using the finite element method. With this method and on-site measurement, the wellhead axial loads of three wells during cement slurry curing were calculated and tested. The results revealed that the maximum relative deviation between the theoretical prediction results by the model and the actual field test data was 10.42%, indicating that the model established is reliable. Finally, using the established finite element calculation method, the effects of the cementing section length on extra loadings on the wellhead were analyzed. This study serves as an accurate reference to calculations of extra loadings on the wellhead during curing of cement slurry and optimization of cementing section length, thus facilitating well cementation. Keywords Casing · Curing of cement slurry · Phase transition · Axial loading · Cementing section length
List of Symbols q ρs ρ i (l) ρ 0 (l) h0 ρ t (l) ρ n (l)
B
Casing mass per unit Density of casing material Density of fluids in the casing (varies with well depth) Density of the medium at depth of l in the casing Length of cementing section Density of pad fluids (varies with well depth) Density of cement slurry (varies with well depth)
Yuqi Ding [email protected] Ye Lu [email protected] Jiahao Cheng [email protected] Min Luo [email protected] Ziwei Dai [email protected]
1
College of Mechanical Science and Engineering, Northeast Petroleum University, Daqing 163318, Heilongjiang, China
As Cross-sectional area of the casing T 0 (h) Stratum temperature (varies with well depth) T (t,h) Casing temperature Casing pressure Pci0 α Well deviation angle Ground annular pressure Pco0 τ (t,l) Gelation strength at well depth h and moment t D Inner diameter of the well wall d Outer diameter of the casing Volume variation ratio S hx Volume contraction coefficient CF Inner large diameter of the casing d ia Inner small diameter of the casing d ib Outer large diameter of the casing d oa Outer small diameter of the casing d ob Outer diameter of casing bottom do Inner diameter of casing bottom di k Heat conduction coefficient Specific heat of cement slurry Cp Q Latent heat of cement slurry solidification T Temperature t Time Volumetric percentage o
Data Loading...
